The present invention generally relates to vehicle seats. More particularly, the present invention pertains to a vehicle seat slide device for holding a vehicle seat device on a vehicle floor in a manner allowing adjustment of the position of the vehicle seat device.
Japanese Patent Publication No. 55 (1980)-26010 discloses a seat slide device that includes a lower rail fixed on the vehicle floor and an upper rail fixed under the seat device. The upper rail slides on the lower rail through the intermediary of rollers. The outer face of the upper portion of the upper rail is welded with the seat device, and the rollers are arranged to contact the inner face of the upper portion of the upper rail. The welding heat causes distortion of the face of the upper rail""s upper portion. This distortion has a tendency to adversely affect the smooth rolling of the rollers and cause an undesirable sliding force increase or large engagement play of the seat slide device.
A need thus exists for a seat slide device for a vehicle which is not susceptible to the same disadvantages and drawbacks as those associated with other known seat devices such as described above.
In light of the foregoing, the present invention provides a seat slide device for a vehicle that includes a lower rail fixed on the floor of the vehicle and an upper rail slidably supported on the lower rail through intermediately located members. The upper rail possesses a horizontal portion having an outer face adapted to be connected with a seat cushion frame and an inner face contacting the intermediately located members. The horizontal portion of the upper rail has a stepped portion dividing the horizontal portion of the upper rail into a connection portion adapted to be connected to the seat cushion frame and a contact portion which contacts the intermediately located members.
According to another aspect of the invention, a seat slide device for a vehicle includes a seat cushion having a seat cushion frame, a lower rail fixed on the floor of the vehicle, and an upper rail slidably supported on the lower rail by way of intermediately located slide permitting members that permit the upper rail to slide relative to the lower rail. The upper rail has a first portion possessing an outside surface facing towards the seat cushion frame. The first portion of the upper rail possesses a connection portion and a contact portion, with the outside surface of the connection portion being connected to the seat cushion frame and the outside surface of the contact portion being elevationally offset from the outside surface of the seat cushion frame to define a clearance between the outside surface of the contact portion and the seat cushion frame.